Normally, a wind turbine blade for a wind turbine comprises an aerodynamic shell made by two shell parts and at least one beam, normally two or three beams, placed between the shell parts and adhered to the inner side of the shell parts by gluing. The beams have a reinforcing function for the turbine blade during operation. The shells are often connected to each other in a trailing edge and a leading edge and normally joined by gluing, alternatively, the shell parts may be integrally formed. The blade further comprises laminates in the shells for reinforcing these shells. The beams absorb large forces during the operation of the blades. Especially the areas close to where the beams are connected to the inside of the shells are subjected to heavy loads which may result in fracture in the beams.
WO 2008/086805 discloses a wind turbine blade provided with an internal reinforcing floor between the trailing edge and the leading edge to improve resistance against de-formation of the shell. This solution increases the complexity of the structure and thus also complexity of manufacture of the blade.
U.S. Pat. No. 5,375,324 discloses a wind turbine blade provided with longitudinally extending I-beams connected to an inner face of blade shell halves. The I-beams are made of fibre-reinforced polymer and are not provided with a beam core of a core material.
WO 2010/023140 discloses a wind turbine blade provided with a longitudinally extending box spar having opposite faces being glued to inner faces of blade shell halves, the glue joints having concave frontline surfaces so as to provide a notch-reducing effect in the glue joints.
JP 61192864 discloses a wind turbine blade formed of three shell parts being mutually connected by means of an adhesive, and a longitudinal beam connected to opposite inner faces of the shell body formed of the three shell parts.
Finally, a wind turbine blade essentially as stated in the preamble to claim 1 is known.